Positive-Pressure Ventilator Systems at High Altitude: A Preliminary Study.
Abstract
The USAF Military Airlift Command is charged with air evacuation of injured and ill patients in times of war and peace. In recent years the types of patients eligible for transport have expanded to include those with illnesses or injuries that require full-time mechanical support of respiratory functions with closed-system positive-pressure mechanical ventilators. The clinical condition of some patients meets the criteria of the Adult Respiratory Distress Syndrome, which is characterized by low pulmonary compliance and poor gas exchange. Respiratory support of such patients in a sea-level environment may require a combination of high-pressure mechanical ventilation and high inspired oxygen tensions. During air evacuation, these patients are routinely exposed to cabin pressures equivalent to 8,000 ft standard atmosphere (564 torr); and during rapid cabin decompression, to pressures equivalent to 40,000 ft standard atmosphere (141 torr). Concern that such environmental situations will exhaust already strained machine and physiological reserves, with potential damage to transported patients, has prompted this evaluation of the effects of altitude on the mechanical performance of ventilators and the functioning of already damaged physiological gas-exchange systems.
Document Details
- Document Type
- Technical Report
- Publication Date
- Jun 01, 1986
- Accession Number
- ADA171647
Entities
People
- Daniel A. Whalen Jr
- Leon E. Farhi
Organizations
- University at Buffalo